51131549 has 6 divisors (see below), whose sum is σ = 59479614. Its totient is φ = 43827000.

The previous prime is 51131543. The next prime is 51131557. The reversal of 51131549 is 94513115.

It can be written as a sum of positive squares in only one way, i.e., 34987225 + 16144324 = 5915^2 + 4018^2 .

It is not a de Polignac number, because 51131549 - 2²⁰ = 50082973 is a prime.

It is a super-2 number, since 2×51131549² = 5228870606278802, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51131543) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 521702 + ... + 521799.

It is an arithmetic number, because the mean of its divisors is an integer number (9913269).

Almost surely, 2^51131549 is an apocalyptic number.

It is an amenable number.

51131549 is a deficient number, since it is larger than the sum of its proper divisors (8348065).

51131549 is a wasteful number, since it uses less digits than its factorization.

51131549 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1043515 (or 1043508 counting only the distinct ones).

The product of its digits is 2700, while the sum is 29.

The square root of 51131549 is about 7150.6327692030. The cubic root of 51131549 is about 371.1615529946.

The spelling of 51131549 in words is "fifty-one million, one hundred thirty-one thousand, five hundred forty-nine".